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    Subject[PATCH 4.19 320/422] x86/CPU: Use correct macros for Cyrix calls
    Date
    From: Matthew Whitehead <tedheadster@gmail.com>

    [ Upstream commit 03b099bdcdf7125d4a63dc9ddeefdd454e05123d ]

    There are comments in processor-cyrix.h advising you to _not_ make calls
    using the deprecated macros in this style:

    setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

    This is because it expands the macro into a non-functioning calling
    sequence. The calling order must be:

    outb(CX86_CCR2, 0x22);
    inb(0x23);

    >From the comments:

    * When using the old macros a line like
    * setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
    * gets expanded to:
    * do {
    * outb((CX86_CCR2), 0x22);
    * outb((({
    * outb((CX86_CCR2), 0x22);
    * inb(0x23);
    * }) | 0x88), 0x23);
    * } while (0);

    The new macros fix this problem, so use them instead.

    Signed-off-by: Matthew Whitehead <tedheadster@gmail.com>
    Signed-off-by: Borislav Petkov <bp@suse.de>
    Reviewed-by: Andy Lutomirski <luto@amacapital.net>
    Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    Cc: "H. Peter Anvin" <hpa@zytor.com>
    Cc: Ingo Molnar <mingo@kernel.org>
    Cc: Jia Zhang <qianyue.zj@alibaba-inc.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Philippe Ombredanne <pombredanne@nexb.com>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Link: http://lkml.kernel.org/r/20180921212041.13096-2-tedheadster@gmail.com
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    arch/x86/kernel/cpu/cyrix.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
    index fa61c870ada94..1d9b8aaea06c8 100644
    --- a/arch/x86/kernel/cpu/cyrix.c
    +++ b/arch/x86/kernel/cpu/cyrix.c
    @@ -437,7 +437,7 @@ static void cyrix_identify(struct cpuinfo_x86 *c)
    /* enable MAPEN */
    setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
    /* enable cpuid */
    - setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);
    + setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x80);
    /* disable MAPEN */
    setCx86(CX86_CCR3, ccr3);
    local_irq_restore(flags);
    --
    2.20.1


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